Edge detection and enhancement techniques are commonly used in recognizing the edge of geologic bodies using potential field data. We present a new edge recognition technology based on the normalized vertical derivati...Edge detection and enhancement techniques are commonly used in recognizing the edge of geologic bodies using potential field data. We present a new edge recognition technology based on the normalized vertical derivative of the total horizontal derivative which has the functions of both edge detection and enhancement techniques. First, we calculate the total horizontal derivative （THDR） of the potential-field data and then compute the n-order vertical derivative （VDRn） of the THDR. For the n-order vertical derivative, the peak value of total horizontal derivative （PTHDR） is obtained using a threshold value greater than 0. This PTHDR can be used for edge detection. Second, the PTHDR value is divided by the total horizontal derivative and normalized by the maximum value. Finally, we used different kinds of numerical models to verify the effectiveness and reliability of the new edge recognition technology.展开更多
Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB p...Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present.展开更多
Impacts of the MJO on winter rainfall and circulation in China are investigated using a real-time multivariate MJO index.Composite results using the daily rainfall anomalies and "rainy day" anomalies accordi...Impacts of the MJO on winter rainfall and circulation in China are investigated using a real-time multivariate MJO index.Composite results using the daily rainfall anomalies and "rainy day" anomalies according to eight different MJO phases show that the MJO has considerable influence on winter rainfall in China. Rainfall anomalies show systematic and substantial changes(enhanced/suppressed) in the Yangtze River Basin and South China with the eastward propagation of the MJO convective center from the Indian Ocean to the western Pacific.When the MJO is in phase 2 and 3(MJO convective center is located over the Indian Ocean),rainfall probability is significantly enhanced.While in phase 6 and 7(MJO convective center is over the western Pacific),rainfall probability is significantly reduced. MJO in winter influences the rainfall in China mainly through modulating the circulation in the subtropics and mid-high latitudes.For the subtropics,MJO influences the northward moisture transport coming from the Bay of Bengal and the South China Sea by modulating the southern trough of the Bay of Bengal and the western Pacific subtropical high.For the mid-high latitudes,the propagation of the low frequency perturbations associated with the eastward-propagating MJO convection modulate the circulation in the mid-high latitudes,e.g.the East Asian winter monsoon and the low trough over central Asia.展开更多
Proper application of nitrogen（N） fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency（NUE）. A lysimeter/rain ...Proper application of nitrogen（N） fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency（NUE）. A lysimeter/rain shelter facility was used to study effects of the rate of N fertilization, type of N fertilizer, and irrigation level on key aspects of winter wheat production over three growing seasons（response variables were nitrate transport, N leaching, and NUE）. Results indicated that nitrate concentration in the soil profile and N leaching increased with the rate of N fertilization. At the end of the third season, nitrate concentration in the top 0–75 cm layer of soil was higher with manure treatment while urea treatments resulted in higher concentrations in the 100–200 cm layer. With normal irrigation, 3.4 to 15.3% of N from applied fertilizer was leached from the soil, yet no leaching occurred under a stress irrigation treatment. The manure treatment experienced less N leaching than the urea treatment in all cases except for the 180 kg N ha^-1 rate in 2011–2012（season 3）. In terms of grain yield（GY）, dry matter（DM） or NUE parameters, values for the manure treatment were lower than for the urea treatment in 2009–2010（season 1）, yet were otherwise higher for urea treatment in season 3. GY and crop nitrogen uptake（NU） were elevated when the rate of N fertilizer increased, while the NUE decreased; GY, DM, and NU increased with the amount of irrigation. Data indicated that reduced rates of N fertilization combined with increased manure application and proper irrigation management can lower nitrate levels in the subsoil and reduce potential N leaching into groundwater.展开更多
目的评价免疫预防措施在实际应用中阻断乙型肝炎病毒（hepatitis B virus，HBV）母婴感染的效果，阐明孕妇孕晚期使用乙肝免疫球蛋白（hepatitis B immunoglobulin，HBIG）能否减少HBV母婴感染。方法将2002年7月至2004年8月江苏省14个...目的评价免疫预防措施在实际应用中阻断乙型肝炎病毒（hepatitis B virus，HBV）母婴感染的效果，阐明孕妇孕晚期使用乙肝免疫球蛋白（hepatitis B immunoglobulin，HBIG）能否减少HBV母婴感染。方法将2002年7月至2004年8月江苏省14个县市的419例乙型肝炎表面抗原（hepatitis Bsurfaceantigen，HBsAg）阳性孕妇所分娩子女作为研究组，同地区同期的453例HBsAg孕妇分娩的子女作为对照组，于2009年10月至2010年3月期间对2组研究对象进行随访，调查母亲孕期HBIG使用情况以及子女出生后HBIG和乙型肝炎疫苗接种情况，检测儿童HBV血清标志物。率的比较采用7。分析或者Fisher精确概率法，均数的比较采用t检验。结果研究组实际随访298例（71．12％），其中11例（3．69％）HBsAg＋；而随访的328例（72．41％）对照组中，HBsAg阳性率为0．00（x2=12．32，P〈0．01）。共11例儿童HBsAg＋，其母亲均为HBsAg和HBeAg同时阳性，除1例具体情况不详外，9例儿童在出生时明确没有使用HBIG或延迟接种疫苗，仅1例同时规范使用了HBIG和乙型肝炎疫苗。2组儿童抗HBs阳性率分别为69．46％和69．21％（x2=0．01，P=0．95）。孕晚期注射HBIG的92例孕妇中，2例（2．17％）儿童HBsAg＋；未使用HBIG的197例孕妇中，9例（4．57％）儿童HBsAg＋（x2=0．98，P=0．51）。结论江苏省常规免疫预防措施在阻断母婴HBV感染方面取得了良好的效果，但对HBV携带孕妇（特别是HBeAg＋者）的新生儿仍需强调及时注射HBIG。孕妇孕晚期使用HBIG不能减少母婴HBV感染。展开更多
The May 12, 2008 Great Wenchuan Earthquake has resulted in more than 68,858 deaths and losses in the hundreds of billions RMB as of May 30, 2008, and these numbers will undoubtedly increase as more information becomes...The May 12, 2008 Great Wenchuan Earthquake has resulted in more than 68,858 deaths and losses in the hundreds of billions RMB as of May 30, 2008, and these numbers will undoubtedly increase as more information becomes available on the extent of the event. Immediately after the earthquake, the China Earthquake Administration （CEA） responded quickly by sending teams of experts to the affected region, eventually including over 60 staff members from the Institute of Engineering Mechanics （IEM）. This paper reports preliminary information that has been gathered in the first 18 days after the event, covering seismicity, search and rescue efforts, observed ground motions, and damage and loss estimates. The extensive field investigation has revealed a number of valuable findings that could be useful in improving research in earthquake engineering in the future. Once again, this earthquake has shown that the vertical component of ground motion is as significant as horizontal ground motions in the near-source area. Finally, note that as more information is gathered, the numbers reported in this paper will need to be adjusted accordingly.展开更多
基金supported by the National Science and Technology Major Projects (2008ZX05025)the Project of National Oil and Gas Resources Strategic Constituency Survey and Evaluation of the Ministry of Land and Resources,China (XQ-2007-05)
文摘Edge detection and enhancement techniques are commonly used in recognizing the edge of geologic bodies using potential field data. We present a new edge recognition technology based on the normalized vertical derivative of the total horizontal derivative which has the functions of both edge detection and enhancement techniques. First, we calculate the total horizontal derivative （THDR） of the potential-field data and then compute the n-order vertical derivative （VDRn） of the THDR. For the n-order vertical derivative, the peak value of total horizontal derivative （PTHDR） is obtained using a threshold value greater than 0. This PTHDR can be used for edge detection. Second, the PTHDR value is divided by the total horizontal derivative and normalized by the maximum value. Finally, we used different kinds of numerical models to verify the effectiveness and reliability of the new edge recognition technology.
文摘Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present.
基金supported by the National Natural Science Foundation of China (40905035)the National Basic Research Program of China (973 Program,Grant No.2010CB428606)+2 种基金the National Department Public Benefit Research Foundation of China(GYHY200806004)the Science Foundation of China(U0833602)the Key Technologies R&D Program of China under Grant Nos.2009BAC51B00 and 2007BAC29B04.
文摘Impacts of the MJO on winter rainfall and circulation in China are investigated using a real-time multivariate MJO index.Composite results using the daily rainfall anomalies and "rainy day" anomalies according to eight different MJO phases show that the MJO has considerable influence on winter rainfall in China. Rainfall anomalies show systematic and substantial changes(enhanced/suppressed) in the Yangtze River Basin and South China with the eastward propagation of the MJO convective center from the Indian Ocean to the western Pacific.When the MJO is in phase 2 and 3(MJO convective center is located over the Indian Ocean),rainfall probability is significantly enhanced.While in phase 6 and 7(MJO convective center is over the western Pacific),rainfall probability is significantly reduced. MJO in winter influences the rainfall in China mainly through modulating the circulation in the subtropics and mid-high latitudes.For the subtropics,MJO influences the northward moisture transport coming from the Bay of Bengal and the South China Sea by modulating the southern trough of the Bay of Bengal and the western Pacific subtropical high.For the mid-high latitudes,the propagation of the low frequency perturbations associated with the eastward-propagating MJO convection modulate the circulation in the mid-high latitudes,e.g.the East Asian winter monsoon and the low trough over central Asia.
基金supported by the National Natural Science Foundation of China(31171497)the European Union’s Seventh Framework Programme(NUE-CROPS 222645)+3 种基金the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2013BAD07B06-2)the Modern Agro-Industry Technology Research System(CARS-02)the Shandong Province Agricultural (Maize) Breeding Project, China(lnlzz2013-1)the Special Fund for Agro-Scientific Research in the Public Interest,China(201203096, 201203100)
文摘Proper application of nitrogen（N） fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency（NUE）. A lysimeter/rain shelter facility was used to study effects of the rate of N fertilization, type of N fertilizer, and irrigation level on key aspects of winter wheat production over three growing seasons（response variables were nitrate transport, N leaching, and NUE）. Results indicated that nitrate concentration in the soil profile and N leaching increased with the rate of N fertilization. At the end of the third season, nitrate concentration in the top 0–75 cm layer of soil was higher with manure treatment while urea treatments resulted in higher concentrations in the 100–200 cm layer. With normal irrigation, 3.4 to 15.3% of N from applied fertilizer was leached from the soil, yet no leaching occurred under a stress irrigation treatment. The manure treatment experienced less N leaching than the urea treatment in all cases except for the 180 kg N ha^-1 rate in 2011–2012（season 3）. In terms of grain yield（GY）, dry matter（DM） or NUE parameters, values for the manure treatment were lower than for the urea treatment in 2009–2010（season 1）, yet were otherwise higher for urea treatment in season 3. GY and crop nitrogen uptake（NU） were elevated when the rate of N fertilizer increased, while the NUE decreased; GY, DM, and NU increased with the amount of irrigation. Data indicated that reduced rates of N fertilization combined with increased manure application and proper irrigation management can lower nitrate levels in the subsoil and reduce potential N leaching into groundwater.
文摘目的评价免疫预防措施在实际应用中阻断乙型肝炎病毒（hepatitis B virus，HBV）母婴感染的效果，阐明孕妇孕晚期使用乙肝免疫球蛋白（hepatitis B immunoglobulin，HBIG）能否减少HBV母婴感染。方法将2002年7月至2004年8月江苏省14个县市的419例乙型肝炎表面抗原（hepatitis Bsurfaceantigen，HBsAg）阳性孕妇所分娩子女作为研究组，同地区同期的453例HBsAg孕妇分娩的子女作为对照组，于2009年10月至2010年3月期间对2组研究对象进行随访，调查母亲孕期HBIG使用情况以及子女出生后HBIG和乙型肝炎疫苗接种情况，检测儿童HBV血清标志物。率的比较采用7。分析或者Fisher精确概率法，均数的比较采用t检验。结果研究组实际随访298例（71．12％），其中11例（3．69％）HBsAg＋；而随访的328例（72．41％）对照组中，HBsAg阳性率为0．00（x2=12．32，P〈0．01）。共11例儿童HBsAg＋，其母亲均为HBsAg和HBeAg同时阳性，除1例具体情况不详外，9例儿童在出生时明确没有使用HBIG或延迟接种疫苗，仅1例同时规范使用了HBIG和乙型肝炎疫苗。2组儿童抗HBs阳性率分别为69．46％和69．21％（x2=0．01，P=0．95）。孕晚期注射HBIG的92例孕妇中，2例（2．17％）儿童HBsAg＋；未使用HBIG的197例孕妇中，9例（4．57％）儿童HBsAg＋（x2=0．98，P=0．51）。结论江苏省常规免疫预防措施在阻断母婴HBV感染方面取得了良好的效果，但对HBV携带孕妇（特别是HBeAg＋者）的新生儿仍需强调及时注射HBIG。孕妇孕晚期使用HBIG不能减少母婴HBV感染。
基金Partially the Project 2007CB714205 of the National Basic Research Program of China
文摘The May 12, 2008 Great Wenchuan Earthquake has resulted in more than 68,858 deaths and losses in the hundreds of billions RMB as of May 30, 2008, and these numbers will undoubtedly increase as more information becomes available on the extent of the event. Immediately after the earthquake, the China Earthquake Administration （CEA） responded quickly by sending teams of experts to the affected region, eventually including over 60 staff members from the Institute of Engineering Mechanics （IEM）. This paper reports preliminary information that has been gathered in the first 18 days after the event, covering seismicity, search and rescue efforts, observed ground motions, and damage and loss estimates. The extensive field investigation has revealed a number of valuable findings that could be useful in improving research in earthquake engineering in the future. Once again, this earthquake has shown that the vertical component of ground motion is as significant as horizontal ground motions in the near-source area. Finally, note that as more information is gathered, the numbers reported in this paper will need to be adjusted accordingly.
